#15938: Hadrian's recompilation check is extremely slow -------------------------------------+------------------------------------- Reporter: bgamari | Owner: alpmestan Type: bug | Status: new Priority: high | Milestone: 8.8.1 Component: Build System | Version: 8.6.2 (Hadrian) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by NeilMitchell): To measure the performance impact of those rules, I did: * {{{--no-build}}} which takes 0.31s * {{{--no-build -VVV}}} which forces it to count (and thus create) all the rules which takes 9.10s So creating the rules takes about 9s on my machine, and is suggestive of the zero-build performance we would gain. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15938#comment:30 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler